On the yun in preinstalled spacebrew, that uses websocket with python. Check this out https://github.com/julioterra/yunSpacebrew

If I get it right from the Spacebrew docu, it uses the serial port to communicate with the python scripts on the Linino site and transfers the data to their cloud hub. But that is not what I want to do. I would like to have an event based API in my sketch and a WebSocket provider on the Linino site. That would be awesome and enable a very reactive web interface to the sketch.

If I get it right from the Spacebrew docu, it uses the serial port to communicate with the python scripts on the Linino site and transfers the data to their cloud hub.

The spacebrew code implements a websocket client. For the Yun a websocket server would be a great addition. I looked at some python implementations but most of them use the gevent package which is not available for OpenWRT.

PyWebsocket might work, looks like they do not use any native code that needs to be cross-compiled.

That sounds good. And how would my data from the Arduino sketch get pasted to the WebSockets server?I would like to have an event handler in my sketch, put some data as a result, and get it past as JSON to my clients JavaScript.

And how would my data from the Arduino sketch get pasted to the WebSockets server?I would like to have an event handler in my sketch, put some data as a result, and get it past as JSON to my clients JavaScript.

There is a forum post which collects some ideas to communicate with a Sketch running on the ATMega from python code running on the linux machine.

The idead would be to send your JSON data from the sketch to the python code over Serial1. Then the python code forwards the data to your Websocket-Client.

With the outline for the pywebsocket code, a typical application would be :

You run the WebSocket server on the Yun

You open a html page with your browser, that brings in the javascript code to open,read and write to the websocket

Some code that is run on the server handles the communication with the Arduino.

Your browser window gets updated by some javascript code that interprets the data returned from the Yun

You're absolutely right, that is exactly what I would like to have/do!I hoped to find this missing link going from Arduino sketch to the Linino out of the box.Plus I would like to see the lib on the Arduino to have an event like registration API.